I apologize if this is in the wrong place. Please move if appropriate.

It seems to be a widespread problem with the 3.x kernels that the ath5k module periodically disconnects and leaves messages about a gain calibration timeout, for me this seems to have been associated with high internet usage. There is a workaround for those interested:

Add pcie_aspm=force to the kernel command line.

I tested this by downloading some data unnecessary data (Ubuntu iso ~700 mb) and so far this workaround has been stable.

EDIT: After a few weeks, I can say this did not entirely solve the problem, but it does make the failures much less frequent. I have only had it happen once or twice since I did this._________________First things first, but not necessarily in that order.

Last edited by The Doctor on Mon Jun 11, 2012 6:53 pm; edited 1 time in total

The kernel parameter pcie_aspm=force activate the Active-State Power Management for all PCIe devices even if they do not support Aspm. It do not take in account the devices performances result. This is what the /usr/src/linux/Documentation/kernel-prameters.txt say:

Code:

pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
Management.
off Disable ASPM.
force Enable ASPM even on devices that claim not to support it.
WARNING: Forcing ASPM on may cause system lockups.

Devices who do not support PCIe ASPM can make a system lockup. It's the reason for the warning. All devices connected to PCIe have to support ASPM to advoid lokups.

Me I use on a desktop computer the pci_aspm=off by the way of

Code:

echo performance > /sys/module/pcie_aspm/parameters/policy

The policy can be one of default (BIOS, EFI, Coreboot, etc settings for all devices), powersave and performance. The one in brakets [] is the active one.

Disable pcie_aspm make the devices connected to PCIe have the best performances. You can try pcie_aspm=off for test and compare with the other policys._________________Paul

Hi everybody,
I check. I pass pcie_aspm=off at the kernel command line and /sys/module/pcie_aspm/parameters/policy is default. So It look that the pcie_aspm kernel parameter do not change the policy in sysfs. So, to change the aspm policy I continue to work with the /sys directory._________________Paul